In the automotive industry, cable sets (or wiring harnesses) are often wrapped with adhesive tapes, whereby, apart from the pure bundling function, mainly textile adhesive tapes provide numerous additional functions, such as protecting the wiring from abrasion, or damping rattling or vibration noises. It has been common to use fabric adhesive tapes as well as various non-woven adhesive tapes, film adhesive tapes and foam adhesive tapes. For the still commonly used helical winding of longitudinally extended products, such as cable sets, bands in which a largely non-adhesive sheath is achieved after sheathing the product are also provided as an alternative to the normally used single-sided full-surface adhesive tapes. Especially by using bands with a double-ply configuration, which can be produced according to a method as described above, whereby two tape plies with lateral projections are laminated one against the other, a significantly greater protection from abrasion and a greater cushioning effect can be accomplished than with single-ply sheathing on the one hand, and on the other hand, these bands, which among other things, are described in DE 20 52 271 A1, and in a further development in EP 1 315 781 B1, have the advantage of a significantly greater flexibility.
The production of these adhesive tapes is not specified in more detail in the above-referenced documents. EP 1 315 781 B1 merely mentions in general that the adhesive tapes are laminated one upon the other such that the adhesive mass of the first carrier material adheres to the adhesive mass of the second carrier material. A production method has, however, been known from the workplace, according to which, in order to ensure the mechanical processability of the adhesive tape plies, operational rolls with the required adhesive tape width are produced in the first instance from supply rolls, onto which the adhesive tape is wound with a great width, so-called wide rolls, which are then laminated laterally offset against one another in a further working step. As these operational rolls have to be prefabricated in the first instance, in particular precut, the method is relatively time and cost intensive.
The underlying object of the invention is to provide a method of the type mentioned above and an apparatus for its implementation, by means of which adhesive tapes can be produced in which a first tape ply can be laminated with its adhesive coating with a lateral projection against the adhesive coating of a second tape ply, whereby the production effort of the adhesive tape can be reduced by ensuring an advantageous economical use of the materials and an easy mechanical processability of the adhesive tape plies.
With respect to the method, it is accomplished according to the present invention in that the carrier material for forming at least one of the tape plies is unwound from a feeding roll, which is configured as a wide roll, on which the carrier material has a greater width than its width required for laminating, and that the carrier material is cut into two strips extending in the longitudinal direction of the band and have the width required for laminating, the strips being separated and laminated such that each strip forms at least one tape ply in respectively at least one adhesive tape.
In this way, an adhesive tape can be produced by means of the invention that on the one hand has a largely non-adhesive internal side and thus advantageously provides the possibility of producing highly flexible sheaths for extended products, like cable sets, but whose production, on the other hand, is simplified insofar as no precut operational rolls are required for this purpose. In particular, the productivity is increased by the parallel production of at least two, and depending on the width of the wide roll, also a plurality of adhesive tapes at the same time. This results in considerable time and thus cost savings compared to the known method.
Furthermore, it is also advantageous that the separate winding rolls—which in particular run at the same speed—onto which the adhesive tapes produced according to the present invention are wound, can be arranged on a common shaft and/or preferentially alternately on two common shafts to separate the strips, for which only one drive is necessary.
With respect to the apparatus, the object of the invention is attained in that at least one feeding roll is configured as a wide roll, on which the carrier material provided with the adhesive coating has a greater width than its width required for laminating, at least one cutting device to cut the carrier material provided with the adhesive coating into strips extending in the longitudinal direction of the band being arranged between the wide roll and the winding roll.
For an optimal selection of the cutting device, e.g. the crush cut system, in which a circular knife works against a roller; the shear cut system, in which a circular knife “dives” into a lower knife; the blade cutting system, in which a stationary blade dives into the transiting product; or the burst cut system, in which a driven circular knife works against a freely guided path, are used. The knives can also be cooled or heated if necessary. Other cutting methods, such as laser cutting or water jet cutting are conceivable. Which cutting method is used depends on the material of the adhesive tapes.
Further advantageous characteristics of the invention are contained in the dependent claims as well as in the description below.